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Combining Heat Stress with Pre-Existing Drought Exacerbated the Effects on Chlorophyll Fluorescence Rise Kinetics in Four Contrasting Plant Species

Date

2021

Authors

Zhu, Lingling
Wen, Wei
Thorpe, Michael
Hocart, Charles
Song, Xin

Journal Title

Journal ISSN

Volume Title

Publisher

MDPI Publishing

Abstract

Although drought and high temperature are two main factors affecting crop productivity and forest vegetation dynamics in many areas worldwide, little work has been done to describe the effects of heat combined with pre-existing drought on photochemical function in diverse plant species. This study investigated the biophysical status of photosystem II (PSII) and its dynamic responses under 2-day heat stress during a 2-week drought by measuring the polyphasic chlorophyll fluorescence rise (OJIP) kinetics. This study examined four contrasting species: a C3 crop/grass (wheat), a C4 crop/grass (sorghum), a temperate tree species (Fraxinus chinensis) and a tropical tree species (Radermachera sinica). Principal component analysis showed that the combination of heat and drought deviated from the effect of heat or drought alone. For all four species, a linear mixed-effects model analysis of variance of the OJIP parameters showed that the deviation arose from decreased quantum yield and increased heat dissipation of PSII. The results confirmed, in four contrasting plant species, that heat stress, when combined with pre-existing drought, exacerbated the effects on PSII photochemistry. These findings provide direction to future research and applications of chlorophyll fluorescence rise OJIP kinetics in agriculture and forestry, for facing increasingly more severe intensity and duration of both heat and drought events under climate change.

Description

Keywords

high temperature, water deficit, photosynthesis, photobiology, fluorescence transient, electron transport

Citation

Source

International Journal of Molecular Sciences

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

License Rights

Creative Commons Attribution licence

DOI

10.3390/ijms221910682

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